The present invention concerns water screens and particularly a rotatable screen for submergence within a body of water.
Water used in various industrial operations must be free of particulate that would clog or at least impede the operation of water using equipment. Recent governmental requirements dictate that water utilized in the industrial operation must meet strict standards prior to return of the water to the stream, river, or other source. Accordingly, many industrial operations have found it economically advisable to recycle large volumes of water with the water being stored in a settling pond or other reservoir. Debris in the body of water in the form of suspended solids above a certain size must be screened or filtered out prior to water reuse. Locationing of a water screen at or near water level incurs the disadvantage of being clogged by a concentration of floating debris while conversely a screen at the lowermost level of a body of water is subjected to a concentration of settled debris.
An additional drawback to known water screens is their complexity and resultant high cost as well as high installation costs attributable to complex support structures.
Water screens within the prior art include that screen disclosed in U.S. Pat. No. 3,843,520 which includes a floating screen component and which includes propulsion nozzles tangentially disposed to the screen. This screen, as well as the screens disclosed in U.S. Pat. Nos. 3,333,700; 3,311,235; 2,685,235 and 2,191,122 includes a backwash system whereby pressurized water is directed through the screen opposite to the filter flow direction for particle dislodgment from the screen exterior.